And the orford copper com



(No Model.)

A J. L. THOMSON.

I APPARATUS FOR HEATING BLAST FORYSHAFT'FURNAQES. No. 377,819.. Patented Feb. 14, 1888.

UNI ED STATES PATENT OFFICE.

JOHN L. THOMSON, OF BERGEN POINT, NEW' JERSEY, ASSIGNOR TO WALTER B. DEVEREUX, OE ASPEN, COLORADO, ANDATHE PANY, OF NEW JERSEY.

ORFORD COPPER ooM APPARATUS FOR HEATING BLAST FOR SHAFT-FURNACES.

SPECIFICATION formingpart of Letters Patent No. 377,819, dated February 14.1.3823.

7 Application filed May 6, 1886. Serial No. 201,261. (No model.)

To all whom itmay'cmwern:

Be it known that I, JOHN L. THOMSON, a subject of the Queen of Great Britain, and a resident of Bergen Point, in thecounty of Hudson and State of New Jersey, have invented certain new and I useful Improvements in Apparatus for Heating Blast for Shaft-Furnaces, of which the following is a specification.

My invention relates "to an apparatus for IO cooling the bed of shaft-furnaces by means of a blast of cold air, which is supplied to the furnace-tuyeres, and of utilizing the heat'which is imparted to the air in this manner for the purpose of heating the blast, and thereby increasing the smelting power of the furnace.

The object of my invention is to afford a ready means of accomplishing this purpose with economy in space and in furnace construction.

In the smelting of copper and other ores it is very often advisable to provide some ready means of cooling the bottom of the furnace, and I have discovered that where the ordinary form of crucible usually employed in blast-furnacesis dispensed with, the bottom of the furnace placed close up the fusion-zone, and a hollow box placed directly under the same, with which box the furnace-tuyeres are connected, I am able, by passing the blastthrough this box dio rectly to the tuyeres, to obtain a great reduction of heat at the furnace-bottom and a considerable degree of heat at the furnace-tuyeres,

and to obtain much more favorable conditions in smelting.

The invention will be best understood by reference to the accompanying drawings, in which i Figure 1 represents a sectional elevation of the furnace on a line drawn at right angles to 0 the direction of the tap-hole, and Fig. 2 a sectional elevation of the furnace on aline drawn lengthwise through the tap-hole.

Similar letters refer to similar parts throughout the several views.

In the views, A represents the ordinary form of shaft-furnace,which is either rectangular or square in cross-section, according to circumstances, with walls composed of firebrick or of water-jackets and with any convenient numher of tuyeres. In the furnace shown in the so the bottom, which may be of fire-brick or other heat and fire resisting material, and may be made fiat, as shown, or so as to inclineslightly toward the tap-hole.

S is the ordinary form of furnace'spout or tap-hole, which may be placed at both sides in '60 cases where the furnace isvery large, thus affording two points of tapping.

The furnace-foundation consists of a hollow metal box, 0, of any convenient construction, resting upon a suitable foundation,M,'as shown in the views. In practice the box will be constructed of flat sections of iron D, provided with the flanges E, and riveted together by the bolts F. The ends' and sides G of the box are made of ordinary plates bolted to the flanges E, or held in position by the weight of the top plates. .At either end of the furnacethe endwalls may be strengthened by introducing into the box a wall of masonry, I. The furnace is supported upon the box 0 by means of any convenient form of guides, preferably, however, by meams of the heavy I-beams J. (Shown in the views.)

T represents the tuyeres, whichare connected with the interior of the box 0 by means of the pipes K, which enter the same at ornear the top, which is the point where the temperature is the greatest, and which are of any of the ordinary patterns, and may be horizontal or slightly inclined,"as shown in the views, as may be found most convenient. A

The cold blast is supplied to the box. by means of the supply-pipe L, which enters-the same at any convenient point, preferably near the bottom, as shown in the views, and is'at- 9o 7 tached at its other extremity to the blowingfan.

The method of operation of the invention is' substantially as follows: As is wellknowmthat portion of a smelting-furnace which is below the fusion-zone will be the hottest portion, and

where the crucible or hearth is dispensed with: j

and a flat bottom is used close up to the fusionsmelting become intensely hot.

zone, that bottom will during the operation of In someform of furnaces now in use an iron bottom is used having a crucible of suflicient depth to collect a small amount of metal below the slag, which metal is tapped oil at intervals separate from the slag. The invention may be applied to this form offurnace in substantially the same manner and with equally good effect. If, now, the air which is supplied to the tuyeres is caused to traverse the bottom of the furnace in its way to the tuyeres, that air will become heated, and its eflicieney for purpose of smelting thereby increased. In my invention the cold blast enters from the blower through the pipe L, and from this pipe is distributed to the tuyere supply-pipes K. The iron sections D D, being on top in direct contact with the bottom of the furnace, become extremely hot, and in turn impart their heat to the sheet-metal heating-boxes. The sections D D may form the bottom of the furnace without any superimposed layer of refractory material, in which case a portion of the charge will be allowed to cool upon the bottom of the furnace, and thus form of itself a refractory layer.

I am aware that it is not new to pass air not under pressure under the bottom or bed of a reverberatory furnace for the purpose of cooling the bed and heating the air as it enters the fire-box, and that it is not new to heat air for cupola-furnaces by passing it through pipes running vertically around the furnace; but I believe, however, that it is new to eliminate the crucible in the bottom of a shaft-furnace and to replace it by a bottom composed of a hollow box, through which the entire volume of the blast passes for the purpose of heating the same. The great advantage of this form of construction consists in the fact that as the bottom of the furnace is perfectly flat and close up to the fusionzone a uniform temperature is maintained at the bottom of the furnace, where- 'by the formation of accretions is avoided and better results are obtained in smelting, and the blast as it passes through the hollow bottom is plied thereto from the blower, and a series of pipes whereby hot blast is supplied to the tuyeres from the said hollow bottom.

2. In a system of heating blast for shaft-furnaces by means of the waste heat of the furnace, the combination, substantially as hereinbefore set forth, with a shaft-furnace, of a hollow bottom constructed wholly or partly of metal for heating the blast supplied to the tuyeres.

Signed at Butte, inthe county of Deer Lodge and Territory of Montana, this 26th day of April, A. D. 1886.

JOHN L. THOMSON.

Witnesses:

W. I. LIPPINCOTT, THOS. H. JUDGE. 

